He was 22 years old, riding his horse south of Corpus Christi in the vicinity of what would one day be called the King Ranch. But that wouldn’t happen for another twenty years.

This vast stretch of sandy prairie was still known as “The Wild Horse Desert.”

In some ways it was a spooky place – ghostly. You would see horse tracks everywhere, but no people. There were plenty of worn trails, but the population was merely equestrian.

Folks reckoned that these horses were the descendants of the ones that arrived with Cortez, when he came to conquer the Aztecs. Some had escaped, migrated north, and bred like rabbits (if you can say that about horses).

Our young man – actually a newly minted second lieutenant from West Point – was riding with a regiment of soldiers under the command of General Zachary Taylor. They were under orders to establish Fort Texas on the Rio Grande and enforce that river as the southern border of the U.S. Fort Texas would shortly become Fort Brown, the fort that Brownsville, Texas would take its name from.

The young lieutenant, who had excelled as a horseman at West Point, was so impressed with the seemingly infinite herds of wild horses in South Texas that he made a note of it in his journal. He said:

“A few days out from Corpus Christi, the immense herd of wild horses that ranged at that time between the Nueces and the Rio Grande was directly in front of us. I rode out a ways to see the extent of the herd. The country was a rolling prairie, and from the higher ground, the vision was obstructed only by the curvature of the earth. As far as the eye could reach to the right, the herd extended. To the left, it extended equally. There was no estimating the number of animals in it; I doubt that they could all have been corralled in the State of Rhode Island, or Delaware, at one time. If they had been, they would have been so thick that the pasture would have given out the first day.”

Both General Taylor and his Second Lieutenant would distinguish themselves on that journey.

Zachary Taylor had no idea that this Wild Horse Desert would lead to him on to victory in Mexico and to political victory back home. He would become the 12th President of the United States.

His dashing second lieutenant would also ascend to the presidency, 20 years after him.

The young man on high ground, surveying the primordial scene of thousands of mustangs grazing before him, would become the hero of many battles in the years ahead. He would ultimately lead the union forces to victory in the Civil War – and become the youngest president of the U.S. His presidential memoirs would become a runaway bestseller – a book Mark Twain would publish and call “the most remarkable work of its kind since Caesar’s Commentaries.” It is that book that gives us this story.

It was written by Hiram U. Grant. Well that was his birth name. But when he entered West Point, due to a clerical error, the name Hiram was dropped and his middle name became his first name, the name you know him by: Ulysses. Ulysses S. Grant.

Listen to the full audio in the player above.

W.F Strong is a Fulbright Scholar and professor of Culture and Communication at the University of Texas Rio Grande Valley. And at Public Radio 88 FM in Harlingen, Texas, he’s the resident expert on Texas literature, Texas legends, Blue Bell Ice Cream, Whataburger (with cheese) and mesquite smoked brisket.